add performance logging on demand, fix minion issues

MareSynchronos/Utils/RollingList.cs

@@ -0,0 +1,46 @@
+using System.Collections;
+
+namespace MareSynchronos.Utils;
+
+public class RollingList<T> : IEnumerable<T>
+{
+    private readonly LinkedList<T> _list = new();
+    private readonly object _addLock = new();
+
+    public RollingList(int maximumCount)
+    {
+        if (maximumCount <= 0)
+            throw new ArgumentException(message: null, nameof(maximumCount));
+
+        MaximumCount = maximumCount;
+    }
+
+    public int MaximumCount { get; }
+    public int Count => _list.Count;
+
+    public void Add(T value)
+    {
+        lock (_addLock)
+        {
+            if (_list.Count == MaximumCount)
+            {
+                _list.RemoveFirst();
+            }
+            _list.AddLast(value);
+        }
+    }
+
+    public T this[int index]
+    {
+        get
+        {
+            if (index < 0 || index >= Count)
+                throw new ArgumentOutOfRangeException(nameof(index));
+
+            return _list.Skip(index).First();
+        }
+    }
+
+    public IEnumerator<T> GetEnumerator() => _list.GetEnumerator();
+    IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
+}